Tube and fitting assemblies have been constructed in many variations. Some have been for hose couplings where a main problem is the high ductility and flexibility of the hose, such as in U.S. Pat. No. 2,447,900. Many have been a multi-part assembly such as a threaded nut and fitting to secure a tube to a fitting and to seal the tube to the fitting and then separately some other second member must be sealed to the fitting. This type is embodied in U.S. Pat. Nos. 2,463,883; 2,545,168. U.S. Pat. No. 3,497,946 relies on three separate operations to expand and contract a tube. U.S. Pat. No. 3,778,090 uses two separate mandrels to expand a tube for sealing with a gasket. U.S. Pat. No. 3,930,298 utilizes longitudinal compression of a tube to seal against a fitting. U.S. Pat. No. 4,076,280 utilizes an expanding tool to expand an end of a conduit inside a fitting having a sharp shoulder to bite into the conduit, and another conduit threads into the fitting. U.S. Pat. No. 4,453,301 teaches how to expand a tube into a header with a sealant therebetween. U.S. Pat. No. 4,669,761 utilizes an expander 30 to expand a tube into sealing engagement with a fitting 14 which then must have a seal at 16 with a mating part. U.S. Pat. No. 4,765,661 teaches a longitudinal compression of a pipe 6 into a fitting tube, and a threaded nut on the fitting holds a second pipe with a seal at a gasket 14. U.S. Pat. No. 4,805,945 has a fitting with a recess and teaches a four-part fitting with a mandrel expanding the tube inside a first fitting.